The present invention was developed expressly for large diameter pipe used for pipeline construction, but the principles are equally applicable to a variety of other elongate material. Large diameter pipe used for pipeline construction is frequently coated with styrene insulation. This insulation is intended to both maintain heat in fluids flowing through the completed pipeline and prevent environmental damage due to heat transference from the pipeline to the ground.
Pipe bending machines used for large diameter pipe are configured in the form of a huge press having two lower supports in spaced relation on which a pipe is supported. An upper pressure member is positioned above and between the two lower supports. A power source is used to cause relative movement of the lower supports and the upper pressure member such that the upper pressure member exerts a bending force upon the pipe.
With the current construction of pipe bending machine the bending force is concentrated at one or two points. Unfortunately, the force which must be exerted by to bend pipe 6 inches in diameter or larger, results in damage to the insulation, which must subsequently be repaired. The larger the diameter of pipe, the greater the bending force required and the more damage which is sustained by the insulation.